I don't believe in memes, but I can understand how memetics might be a useful way of thinking how particular ideas change over time in gradual ways, and how they compete with other similar ideas.
It's not really productive to think of genes as selfish, although that is how Dawkins chooses to present it metaphorically. It is just that certain genes may be in competition with the fitness of the organism they are carried in. For example, the genes that cause worker ants to forgo reproduction and put all their energy into feeding the queen and future queens. In this sense it is not the genes of the individual ants clearly do not benefit the individual organism, they benefit the queen, or themselves. How can these types of social organisations develop, the answer is genes which favour their own selection over the selection of the individual.
I personally think selection operates at several levels, from the gene level (the selfish gene concept), to the organismal and possibly the group level (although it is arguable that group selection is redundant and anything explained by group selection can be explained by selection of individuals, and in turn it is arguable that gene selection renders the selection of individuals redundant). If we think of selection operating at the level of the gene, even when they are genes that survive because they allow the organism they are found in to survive, it explains the same thing as looking merely at the selection at the level of the organism. These things are not actually separate concepts, but different perspectives on the same mechanism of natural selection. Ultimately, gene-centric selection explains more than older models, that is why it has grown to become dominant in the biological sciences, when it was perhaps about 50/50 back in the 70s when Dawkins first published the Selfish Gene.
In essence the concept of a "selfish gene" is no different than the concept of a selfish individual.
Now for the question of the evolution of sexual selection. This is a place where we might look at how selection at the level of the organism may be more explicative than selection at the level of the gene. Because, as conventional wisdom goes, populations with sexual reproduction are capable of evolving faster and dealing with environmental change better than asexual reproductive organisms, so they out compete most asexual organisms. This is just with complex eukaryotes though. Even some bacteria reproduce sexually, except they swap genes with each other directly without producing offspring. Although, I'm not sure sexual reproduction can't also be explained by gene-centric selection, for example the genes involved in sexual selection certainly benefit from the success of the phenomenon, even if perhaps individual alleles don't benefit from possibly being left out of the reproductive line by the randomness of the meiotic process.